JsonCpp parse issue

[gedinfo]

I have created a .json file, and need to read it and append some new information to it.
This is in JsonCpp library, and I have no issue creating the new information, but when I attempt to append to the .json file, I get a LogicError related message.

Here is the actual line causing problems:

json_obj.append(root);

root is the new information, json_obj is the read in from the .json file data.

Does anyone have any suggestions on how to properly handle this, as I have additional updates to the .json related to appending to perform.

Thank you.

[helios]

I'm not sure what you expect from us. Without knowing the types of json_obj and root, that line is completely meaningless.

[Ganado]

You should create a minimal compileable example (even better if it's just using strings instead of working with files). And link the github or whatever to your library.

[gedinfo]

Json::Value is the type for both.

[George P]

Our crystal balls are busted, we don't have a clue what is going on without providing us with a compileable example and a lot more information.

[helios]

OP, why are you carefully choosing your words to provide the minimum information possible? Are you trying to deliberately waste our time and don't really care if your question gets answered?

[gedinfo]

#include <json/json.h>
#include <stdio.h>
#include <fstream>

Json::StreamWriterBuilder jswb;

char gfilename[BUFSIZ];
strcpy (gfilename, "gfile.json"); // original json file
        
std::fstream json_file;
Json::Value root(Json::arrayValue); // contains some additional json info to append
Json::Value json_obj;
json_file.open(gfilename, std::ios_base::in);    

json_file >> json_obj; // parsed json file read from file
json_file.close();
// append to json object
json_obj.append(root);
    
// write updated json object to file
json_file.open(gfilename, std::ios::out);
jswb["indentation"]="";

std::string jsonMsg = Json::writeString(jswb,json_obj) + "\n";
json_file << jsonMsg;
json_file.close();

[George P]

Stilll no self-contained compileable example, as was previously and politely requested. Not SSCCE.

http://www.sscce.org/

You want suggestions....

Do what you are asked to do. Provide code we can compile, run and observe ourselves.